Why did so many european immigrants come to the us in the 1800s

After the Civil War, immigrants again began to stream to the United
States. Between 1870 and 1900, nearly 12 million immigrants
arrived–more foreign-born people than had come to the country in the
preceding 70 years. During the 1870s and 1880s, the majority came from
Germany, Ireland, and England–the principal source of immigration
before the Civil War. Even so, a relatively large group of Chinese
immigrated to the United States between the start of the California gold
rush in 1849 and 1882, when federal law stopped their immigration.

While the majority of immigrants came to settle in the United States
permanently, many worked for a time and returned home with whatever
savings they had set aside from their work. The majority of Chinese
immigrants, for example, were single men who worked for a while and
returned home. At first, they were attracted to North America by the
gold rush in California. Many prospected for gold on their own or
labored for other miners. Soon, many opened their own businesses such as
restaurants, laundries, and other personal service concerns. After the
gold rush, Chinese immigrants worked as agricultural laborers, on
railroad construction crews throughout the West, and in low-paying
industrial jobs.

With the onset of hard economic times in the 1870s, other immigrants
and European Americans began to compete for the jobs traditionally
reserved for the Chinese. With economic competition came dislike and
even racial suspicion and hatred. Such feelings were accompanied by
anti-Chinese riots and pressure, especially in California, for the
exclusion of Chinese immigrants from the United States. The result of
this pressure was the Chinese Exclusion Act, passed by Congress in 1882.
This Act virtually ended Chinese immigration for nearly a century. As
the following documents suggest, there were many opinions about this
issue.